2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
20 #include <linux/pagemap.h>
21 #include <linux/highmem.h>
22 #include <linux/time.h>
23 #include <linux/init.h>
24 #include <linux/string.h>
25 #include <linux/smp_lock.h>
26 #include <linux/backing-dev.h>
27 #include <linux/mpage.h>
28 #include <linux/swap.h>
29 #include <linux/writeback.h>
30 #include <linux/statfs.h>
31 #include <linux/compat.h>
32 #include <linux/version.h>
35 #include "transaction.h"
36 #include "btrfs_inode.h"
37 #include "ordered-data.h"
39 #include "print-tree.h"
43 static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
44 struct page **prepared_pages,
45 const char __user * buf)
49 int offset = pos & (PAGE_CACHE_SIZE - 1);
51 for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) {
52 size_t count = min_t(size_t,
53 PAGE_CACHE_SIZE - offset, write_bytes);
54 struct page *page = prepared_pages[i];
55 fault_in_pages_readable(buf, count);
57 /* Copy data from userspace to the current page */
59 page_fault = __copy_from_user(page_address(page) + offset,
61 /* Flush processor's dcache for this page */
62 flush_dcache_page(page);
70 return page_fault ? -EFAULT : 0;
73 static void btrfs_drop_pages(struct page **pages, size_t num_pages)
76 for (i = 0; i < num_pages; i++) {
79 unlock_page(pages[i]);
80 mark_page_accessed(pages[i]);
81 page_cache_release(pages[i]);
85 static int noinline insert_inline_extent(struct btrfs_trans_handle *trans,
86 struct btrfs_root *root, struct inode *inode,
87 u64 offset, size_t size,
88 struct page **pages, size_t page_offset,
92 struct btrfs_path *path;
93 struct extent_buffer *leaf;
96 struct btrfs_file_extent_item *ei;
104 path = btrfs_alloc_path();
108 btrfs_set_trans_block_group(trans, inode);
110 key.objectid = inode->i_ino;
112 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
114 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
120 struct btrfs_key found_key;
122 if (path->slots[0] == 0)
126 leaf = path->nodes[0];
127 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
129 if (found_key.objectid != inode->i_ino)
132 if (found_key.type != BTRFS_EXTENT_DATA_KEY)
134 ei = btrfs_item_ptr(leaf, path->slots[0],
135 struct btrfs_file_extent_item);
137 if (btrfs_file_extent_type(leaf, ei) !=
138 BTRFS_FILE_EXTENT_INLINE) {
141 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
148 leaf = path->nodes[0];
149 ei = btrfs_item_ptr(leaf, path->slots[0],
150 struct btrfs_file_extent_item);
152 if (btrfs_file_extent_type(leaf, ei) !=
153 BTRFS_FILE_EXTENT_INLINE) {
155 btrfs_print_leaf(root, leaf);
156 printk("found wasn't inline offset %Lu inode %lu\n",
157 offset, inode->i_ino);
160 found_size = btrfs_file_extent_inline_len(leaf,
161 btrfs_item_nr(leaf, path->slots[0]));
162 found_end = key.offset + found_size;
164 if (found_end < offset + size) {
165 btrfs_release_path(root, path);
166 ret = btrfs_search_slot(trans, root, &key, path,
167 offset + size - found_end, 1);
170 ret = btrfs_extend_item(trans, root, path,
171 offset + size - found_end);
176 leaf = path->nodes[0];
177 ei = btrfs_item_ptr(leaf, path->slots[0],
178 struct btrfs_file_extent_item);
179 inode->i_blocks += (offset + size - found_end) >> 9;
181 if (found_end < offset) {
182 ptr = btrfs_file_extent_inline_start(ei) + found_size;
183 memset_extent_buffer(leaf, 0, ptr, offset - found_end);
187 btrfs_release_path(root, path);
188 datasize = offset + size - key.offset;
189 inode->i_blocks += datasize >> 9;
190 datasize = btrfs_file_extent_calc_inline_size(datasize);
191 ret = btrfs_insert_empty_item(trans, root, path, &key,
195 printk("got bad ret %d\n", ret);
198 leaf = path->nodes[0];
199 ei = btrfs_item_ptr(leaf, path->slots[0],
200 struct btrfs_file_extent_item);
201 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
202 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
204 ptr = btrfs_file_extent_inline_start(ei) + offset - key.offset;
210 kaddr = kmap_atomic(page, KM_USER0);
211 cur_size = min_t(size_t, PAGE_CACHE_SIZE - page_offset, size);
212 write_extent_buffer(leaf, kaddr + page_offset, ptr, cur_size);
213 kunmap_atomic(kaddr, KM_USER0);
217 if (i >= num_pages) {
218 printk("i %d num_pages %d\n", i, num_pages);
222 btrfs_mark_buffer_dirty(leaf);
224 btrfs_free_path(path);
228 static int noinline dirty_and_release_pages(struct btrfs_trans_handle *trans,
229 struct btrfs_root *root,
238 struct inode *inode = fdentry(file)->d_inode;
239 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
243 u64 end_of_last_block;
244 u64 end_pos = pos + write_bytes;
246 loff_t isize = i_size_read(inode);
248 start_pos = pos & ~((u64)root->sectorsize - 1);
249 num_bytes = (write_bytes + pos - start_pos +
250 root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
252 end_of_last_block = start_pos + num_bytes - 1;
254 lock_extent(io_tree, start_pos, end_of_last_block, GFP_NOFS);
255 mutex_lock(&root->fs_info->fs_mutex);
256 trans = btrfs_start_transaction(root, 1);
261 btrfs_set_trans_block_group(trans, inode);
264 if ((end_of_last_block & 4095) == 0) {
265 printk("strange end of last %Lu %zu %Lu\n", start_pos, write_bytes, end_of_last_block);
267 set_extent_uptodate(io_tree, start_pos, end_of_last_block, GFP_NOFS);
269 /* FIXME...EIEIO, ENOSPC and more */
270 /* insert any holes we need to create */
271 if (isize < end_pos) {
272 u64 last_pos_in_file;
274 u64 mask = root->sectorsize - 1;
275 last_pos_in_file = (isize + mask) & ~mask;
276 hole_size = (end_pos - last_pos_in_file + mask) & ~mask;
277 if (last_pos_in_file < end_pos) {
278 err = btrfs_drop_extents(trans, root, inode,
280 last_pos_in_file + hole_size,
286 err = btrfs_insert_file_extent(trans, root,
290 btrfs_drop_extent_cache(inode, last_pos_in_file,
291 last_pos_in_file + hole_size -1);
292 btrfs_check_file(root, inode);
299 * either allocate an extent for the new bytes or setup the key
300 * to show we are doing inline data in the extent
302 inline_size = end_pos;
303 if (isize >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
304 inline_size > root->fs_info->max_inline ||
305 (inline_size & (root->sectorsize -1)) == 0 ||
306 inline_size >= BTRFS_MAX_INLINE_DATA_SIZE(root)) {
309 for (i = 0; i < num_pages; i++) {
310 struct page *p = pages[i];
314 last_end = (u64)(pages[num_pages -1]->index) <<
316 last_end += PAGE_CACHE_SIZE - 1;
317 set_extent_delalloc(io_tree, start_pos, end_of_last_block,
319 btrfs_add_ordered_inode(inode);
322 /* step one, delete the existing extents in this range */
323 aligned_end = (pos + write_bytes + root->sectorsize - 1) &
324 ~((u64)root->sectorsize - 1);
325 err = btrfs_drop_extents(trans, root, inode, start_pos,
326 aligned_end, aligned_end, &hint_byte);
329 if (isize > inline_size)
330 inline_size = min_t(u64, isize, aligned_end);
331 inline_size -= start_pos;
332 err = insert_inline_extent(trans, root, inode, start_pos,
333 inline_size, pages, 0, num_pages);
334 btrfs_drop_extent_cache(inode, start_pos, aligned_end - 1);
337 if (end_pos > isize) {
338 i_size_write(inode, end_pos);
339 btrfs_update_inode(trans, root, inode);
342 err = btrfs_end_transaction(trans, root);
344 mutex_unlock(&root->fs_info->fs_mutex);
345 unlock_extent(io_tree, start_pos, end_of_last_block, GFP_NOFS);
349 int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end)
351 struct extent_map *em;
352 struct extent_map *split = NULL;
353 struct extent_map *split2 = NULL;
354 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
355 u64 len = end - start + 1;
359 if (end == (u64)-1) {
365 split = alloc_extent_map(GFP_NOFS);
367 split2 = alloc_extent_map(GFP_NOFS);
369 spin_lock(&em_tree->lock);
370 em = lookup_extent_mapping(em_tree, start, len);
372 spin_unlock(&em_tree->lock);
375 remove_extent_mapping(em_tree, em);
377 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
379 split->start = em->start;
380 split->len = start - em->start;
381 split->block_start = em->block_start;
382 split->bdev = em->bdev;
383 split->flags = em->flags;
384 ret = add_extent_mapping(em_tree, split);
386 free_extent_map(split);
390 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
391 testend && em->start + em->len > start + len) {
392 u64 diff = start + len - em->start;
394 split->start = start + len;
395 split->len = em->start + em->len - (start + len);
396 split->bdev = em->bdev;
397 split->flags = em->flags;
399 split->block_start = em->block_start + diff;
401 ret = add_extent_mapping(em_tree, split);
403 free_extent_map(split);
406 spin_unlock(&em_tree->lock);
410 /* once for the tree*/
414 free_extent_map(split);
416 free_extent_map(split2);
420 int btrfs_check_file(struct btrfs_root *root, struct inode *inode)
424 struct btrfs_path *path;
425 struct btrfs_key found_key;
426 struct extent_buffer *leaf;
427 struct btrfs_file_extent_item *extent;
436 path = btrfs_alloc_path();
437 ret = btrfs_lookup_file_extent(NULL, root, path, inode->i_ino,
440 nritems = btrfs_header_nritems(path->nodes[0]);
441 if (path->slots[0] >= nritems) {
442 ret = btrfs_next_leaf(root, path);
445 nritems = btrfs_header_nritems(path->nodes[0]);
447 slot = path->slots[0];
448 leaf = path->nodes[0];
449 btrfs_item_key_to_cpu(leaf, &found_key, slot);
450 if (found_key.objectid != inode->i_ino)
452 if (found_key.type != BTRFS_EXTENT_DATA_KEY)
455 if (found_key.offset < last_offset) {
457 btrfs_print_leaf(root, leaf);
458 printk("inode %lu found offset %Lu expected %Lu\n",
459 inode->i_ino, found_key.offset, last_offset);
463 extent = btrfs_item_ptr(leaf, slot,
464 struct btrfs_file_extent_item);
465 found_type = btrfs_file_extent_type(leaf, extent);
466 if (found_type == BTRFS_FILE_EXTENT_REG) {
467 extent_end = found_key.offset +
468 btrfs_file_extent_num_bytes(leaf, extent);
469 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
470 struct btrfs_item *item;
471 item = btrfs_item_nr(leaf, slot);
472 extent_end = found_key.offset +
473 btrfs_file_extent_inline_len(leaf, item);
474 extent_end = (extent_end + root->sectorsize - 1) &
475 ~((u64)root->sectorsize -1 );
477 last_offset = extent_end;
480 if (0 && last_offset < inode->i_size) {
482 btrfs_print_leaf(root, leaf);
483 printk("inode %lu found offset %Lu size %Lu\n", inode->i_ino,
484 last_offset, inode->i_size);
489 btrfs_free_path(path);
495 * this is very complex, but the basic idea is to drop all extents
496 * in the range start - end. hint_block is filled in with a block number
497 * that would be a good hint to the block allocator for this file.
499 * If an extent intersects the range but is not entirely inside the range
500 * it is either truncated or split. Anything entirely inside the range
501 * is deleted from the tree.
503 int btrfs_drop_extents(struct btrfs_trans_handle *trans,
504 struct btrfs_root *root, struct inode *inode,
505 u64 start, u64 end, u64 inline_limit, u64 *hint_byte)
508 u64 search_start = start;
509 struct extent_buffer *leaf;
510 struct btrfs_file_extent_item *extent;
511 struct btrfs_path *path;
512 struct btrfs_key key;
513 struct btrfs_file_extent_item old;
523 btrfs_drop_extent_cache(inode, start, end - 1);
525 path = btrfs_alloc_path();
530 btrfs_release_path(root, path);
531 ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
536 if (path->slots[0] == 0) {
548 leaf = path->nodes[0];
549 slot = path->slots[0];
551 btrfs_item_key_to_cpu(leaf, &key, slot);
552 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY &&
556 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
557 key.objectid != inode->i_ino) {
561 search_start = key.offset;
564 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
565 extent = btrfs_item_ptr(leaf, slot,
566 struct btrfs_file_extent_item);
567 found_type = btrfs_file_extent_type(leaf, extent);
568 if (found_type == BTRFS_FILE_EXTENT_REG) {
570 btrfs_file_extent_disk_bytenr(leaf,
573 *hint_byte = extent_end;
575 extent_end = key.offset +
576 btrfs_file_extent_num_bytes(leaf, extent);
578 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
579 struct btrfs_item *item;
580 item = btrfs_item_nr(leaf, slot);
582 extent_end = key.offset +
583 btrfs_file_extent_inline_len(leaf, item);
586 extent_end = search_start;
589 /* we found nothing we can drop */
590 if ((!found_extent && !found_inline) ||
591 search_start >= extent_end) {
594 nritems = btrfs_header_nritems(leaf);
595 if (slot >= nritems - 1) {
596 nextret = btrfs_next_leaf(root, path);
607 u64 mask = root->sectorsize - 1;
608 search_start = (extent_end + mask) & ~mask;
610 search_start = extent_end;
611 if (end <= extent_end && start >= key.offset && found_inline) {
612 *hint_byte = EXTENT_MAP_INLINE;
615 if (end < extent_end && end >= key.offset) {
618 btrfs_file_extent_disk_bytenr(leaf, extent);
620 btrfs_file_extent_disk_num_bytes(leaf,
622 read_extent_buffer(leaf, &old,
623 (unsigned long)extent,
625 if (disk_bytenr != 0) {
626 ret = btrfs_inc_extent_ref(trans, root,
627 disk_bytenr, disk_num_bytes,
628 root->root_key.objectid,
635 if (found_inline && start <= key.offset)
638 /* truncate existing extent */
639 if (start > key.offset) {
643 WARN_ON(start & (root->sectorsize - 1));
645 new_num = start - key.offset;
646 old_num = btrfs_file_extent_num_bytes(leaf,
649 btrfs_file_extent_disk_bytenr(leaf,
651 if (btrfs_file_extent_disk_bytenr(leaf,
653 dec_i_blocks(inode, old_num - new_num);
655 btrfs_set_file_extent_num_bytes(leaf, extent,
657 btrfs_mark_buffer_dirty(leaf);
658 } else if (key.offset < inline_limit &&
659 (end > extent_end) &&
660 (inline_limit < extent_end)) {
662 new_size = btrfs_file_extent_calc_inline_size(
663 inline_limit - key.offset);
664 dec_i_blocks(inode, (extent_end - key.offset) -
665 (inline_limit - key.offset));
666 btrfs_truncate_item(trans, root, path,
670 /* delete the entire extent */
673 u64 disk_num_bytes = 0;
674 u64 extent_num_bytes = 0;
678 root_gen = btrfs_header_generation(leaf);
679 root_owner = btrfs_header_owner(leaf);
682 btrfs_file_extent_disk_bytenr(leaf,
685 btrfs_file_extent_disk_num_bytes(leaf,
688 btrfs_file_extent_num_bytes(leaf, extent);
690 btrfs_file_extent_disk_bytenr(leaf,
693 ret = btrfs_del_item(trans, root, path);
694 /* TODO update progress marker and return */
696 btrfs_release_path(root, path);
698 if (found_extent && disk_bytenr != 0) {
699 dec_i_blocks(inode, extent_num_bytes);
700 ret = btrfs_free_extent(trans, root,
704 root_gen, inode->i_ino,
709 if (!bookend && search_start >= end) {
716 if (bookend && found_inline && start <= key.offset) {
718 new_size = btrfs_file_extent_calc_inline_size(
720 dec_i_blocks(inode, (extent_end - key.offset) -
722 btrfs_truncate_item(trans, root, path, new_size, 0);
724 /* create bookend, splitting the extent in two */
725 if (bookend && found_extent) {
726 struct btrfs_key ins;
727 ins.objectid = inode->i_ino;
729 btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY);
730 btrfs_release_path(root, path);
731 ret = btrfs_insert_empty_item(trans, root, path, &ins,
734 leaf = path->nodes[0];
736 btrfs_print_leaf(root, leaf);
737 printk("got %d on inserting %Lu %u %Lu start %Lu end %Lu found %Lu %Lu keep was %d\n", ret , ins.objectid, ins.type, ins.offset, start, end, key.offset, extent_end, keep);
740 extent = btrfs_item_ptr(leaf, path->slots[0],
741 struct btrfs_file_extent_item);
742 write_extent_buffer(leaf, &old,
743 (unsigned long)extent, sizeof(old));
745 btrfs_set_file_extent_offset(leaf, extent,
746 le64_to_cpu(old.offset) + end - key.offset);
747 WARN_ON(le64_to_cpu(old.num_bytes) <
749 btrfs_set_file_extent_num_bytes(leaf, extent,
751 btrfs_set_file_extent_type(leaf, extent,
752 BTRFS_FILE_EXTENT_REG);
754 btrfs_mark_buffer_dirty(path->nodes[0]);
755 if (le64_to_cpu(old.disk_bytenr) != 0) {
757 btrfs_file_extent_num_bytes(leaf,
765 btrfs_free_path(path);
766 btrfs_check_file(root, inode);
771 * this gets pages into the page cache and locks them down
773 static int prepare_pages(struct btrfs_root *root, struct file *file,
774 struct page **pages, size_t num_pages,
775 loff_t pos, unsigned long first_index,
776 unsigned long last_index, size_t write_bytes)
779 unsigned long index = pos >> PAGE_CACHE_SHIFT;
780 struct inode *inode = fdentry(file)->d_inode;
784 start_pos = pos & ~((u64)root->sectorsize - 1);
786 memset(pages, 0, num_pages * sizeof(struct page *));
788 for (i = 0; i < num_pages; i++) {
789 pages[i] = grab_cache_page(inode->i_mapping, index + i);
794 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
795 ClearPageDirty(pages[i]);
797 cancel_dirty_page(pages[i], PAGE_CACHE_SIZE);
799 wait_on_page_writeback(pages[i]);
800 set_page_extent_mapped(pages[i]);
801 WARN_ON(!PageLocked(pages[i]));
803 if (start_pos < inode->i_size) {
805 last_pos = ((u64)index + num_pages) << PAGE_CACHE_SHIFT;
806 lock_extent(&BTRFS_I(inode)->io_tree,
807 start_pos, last_pos - 1, GFP_NOFS);
808 clear_extent_bits(&BTRFS_I(inode)->io_tree, start_pos,
809 last_pos - 1, EXTENT_DIRTY | EXTENT_DELALLOC,
811 unlock_extent(&BTRFS_I(inode)->io_tree,
812 start_pos, last_pos - 1, GFP_NOFS);
817 static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
818 size_t count, loff_t *ppos)
822 ssize_t num_written = 0;
825 struct inode *inode = fdentry(file)->d_inode;
826 struct btrfs_root *root = BTRFS_I(inode)->root;
827 struct page **pages = NULL;
829 struct page *pinned[2];
830 unsigned long first_index;
831 unsigned long last_index;
833 nrptrs = min((count + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE,
834 PAGE_CACHE_SIZE / (sizeof(struct page *)));
841 vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
842 current->backing_dev_info = inode->i_mapping->backing_dev_info;
843 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
848 #ifdef REMOVE_SUID_PATH
849 err = remove_suid(&file->f_path);
851 err = remove_suid(fdentry(file));
855 file_update_time(file);
857 pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
859 mutex_lock(&inode->i_mutex);
860 first_index = pos >> PAGE_CACHE_SHIFT;
861 last_index = (pos + count) >> PAGE_CACHE_SHIFT;
864 * if this is a nodatasum mount, force summing off for the inode
865 * all the time. That way a later mount with summing on won't
868 if (btrfs_test_opt(root, NODATASUM))
869 btrfs_set_flag(inode, NODATASUM);
872 * there are lots of better ways to do this, but this code
873 * makes sure the first and last page in the file range are
874 * up to date and ready for cow
876 if ((pos & (PAGE_CACHE_SIZE - 1))) {
877 pinned[0] = grab_cache_page(inode->i_mapping, first_index);
878 if (!PageUptodate(pinned[0])) {
879 ret = btrfs_readpage(NULL, pinned[0]);
881 wait_on_page_locked(pinned[0]);
883 unlock_page(pinned[0]);
886 if ((pos + count) & (PAGE_CACHE_SIZE - 1)) {
887 pinned[1] = grab_cache_page(inode->i_mapping, last_index);
888 if (!PageUptodate(pinned[1])) {
889 ret = btrfs_readpage(NULL, pinned[1]);
891 wait_on_page_locked(pinned[1]);
893 unlock_page(pinned[1]);
898 size_t offset = pos & (PAGE_CACHE_SIZE - 1);
899 size_t write_bytes = min(count, nrptrs *
900 (size_t)PAGE_CACHE_SIZE -
902 size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
905 WARN_ON(num_pages > nrptrs);
906 memset(pages, 0, sizeof(pages));
908 mutex_lock(&root->fs_info->fs_mutex);
909 ret = btrfs_check_free_space(root, write_bytes, 0);
910 mutex_unlock(&root->fs_info->fs_mutex);
914 ret = prepare_pages(root, file, pages, num_pages,
915 pos, first_index, last_index,
920 ret = btrfs_copy_from_user(pos, num_pages,
921 write_bytes, pages, buf);
923 btrfs_drop_pages(pages, num_pages);
927 ret = dirty_and_release_pages(NULL, root, file, pages,
928 num_pages, pos, write_bytes);
929 btrfs_drop_pages(pages, num_pages);
934 count -= write_bytes;
936 num_written += write_bytes;
938 balance_dirty_pages_ratelimited_nr(inode->i_mapping, num_pages);
939 if (num_pages < (root->leafsize >> PAGE_CACHE_SHIFT) + 1)
940 btrfs_btree_balance_dirty(root, 1);
941 btrfs_throttle(root);
945 mutex_unlock(&inode->i_mutex);
950 page_cache_release(pinned[0]);
952 page_cache_release(pinned[1]);
955 if (num_written > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
956 err = sync_page_range(inode, inode->i_mapping,
957 start_pos, num_written);
960 } else if (num_written > 0 && (file->f_flags & O_DIRECT)) {
961 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,22)
962 do_sync_file_range(file, start_pos,
963 start_pos + num_written - 1,
964 SYNC_FILE_RANGE_WRITE |
965 SYNC_FILE_RANGE_WAIT_AFTER);
967 do_sync_mapping_range(inode->i_mapping, start_pos,
968 start_pos + num_written - 1,
969 SYNC_FILE_RANGE_WRITE |
970 SYNC_FILE_RANGE_WAIT_AFTER);
972 invalidate_mapping_pages(inode->i_mapping,
973 start_pos >> PAGE_CACHE_SHIFT,
974 (start_pos + num_written - 1) >> PAGE_CACHE_SHIFT);
976 current->backing_dev_info = NULL;
977 btrfs_ordered_throttle(root, inode);
978 return num_written ? num_written : err;
981 static int btrfs_release_file (struct inode * inode, struct file * filp)
983 btrfs_del_ordered_inode(inode);
987 static int btrfs_sync_file(struct file *file,
988 struct dentry *dentry, int datasync)
990 struct inode *inode = dentry->d_inode;
991 struct btrfs_root *root = BTRFS_I(inode)->root;
993 struct btrfs_trans_handle *trans;
996 * check the transaction that last modified this inode
997 * and see if its already been committed
999 mutex_lock(&root->fs_info->fs_mutex);
1000 if (!BTRFS_I(inode)->last_trans)
1002 mutex_lock(&root->fs_info->trans_mutex);
1003 if (BTRFS_I(inode)->last_trans <=
1004 root->fs_info->last_trans_committed) {
1005 BTRFS_I(inode)->last_trans = 0;
1006 mutex_unlock(&root->fs_info->trans_mutex);
1009 mutex_unlock(&root->fs_info->trans_mutex);
1012 * ok we haven't committed the transaction yet, lets do a commit
1014 trans = btrfs_start_transaction(root, 1);
1019 ret = btrfs_commit_transaction(trans, root);
1021 mutex_unlock(&root->fs_info->fs_mutex);
1022 return ret > 0 ? EIO : ret;
1025 static struct vm_operations_struct btrfs_file_vm_ops = {
1026 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
1027 .nopage = filemap_nopage,
1028 .populate = filemap_populate,
1030 .fault = filemap_fault,
1032 .page_mkwrite = btrfs_page_mkwrite,
1035 static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma)
1037 vma->vm_ops = &btrfs_file_vm_ops;
1038 file_accessed(filp);
1042 struct file_operations btrfs_file_operations = {
1043 .llseek = generic_file_llseek,
1044 .read = do_sync_read,
1045 .aio_read = generic_file_aio_read,
1046 .splice_read = generic_file_splice_read,
1047 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
1048 .sendfile = generic_file_sendfile,
1050 .write = btrfs_file_write,
1051 .mmap = btrfs_file_mmap,
1052 .open = generic_file_open,
1053 .release = btrfs_release_file,
1054 .fsync = btrfs_sync_file,
1055 .unlocked_ioctl = btrfs_ioctl,
1056 #ifdef CONFIG_COMPAT
1057 .compat_ioctl = btrfs_ioctl,